Sesquiterpene Lactones in Cynara: Biological Activities, Agriculture Applications, Extraction Techniques, and Production Enhancement Strategies

The genus Cynara is native to the Mediterranean region and is widely used in food and traditional medicine worldwide. Cynara is characterized by its diverse phytochemical composition, with sesquiterpene lactones, a subclass of terpenoids, being particularly distinctive. These compounds are naturally synthesized as defense mechanisms against herbivores and pathogens while acting as allelochemicals. The sesquiterpene lactones found in Cynara exhibit potential anticancer, anti-inflammatory, and antimicrobial activities. They also possess significant phytotoxic activity, making them promising natural bioherbicides for agricultural applications. The effective exploitation of these compounds requires the use of appropriate extraction solvents and techniques. Compared with conventional solvents and extraction methods, green solvents, including ionic liquids and deep eutectic solvents, together with modern extraction techniques, particularly ultrasound-assisted extraction, supercritical fluid extraction, and Naviglio extraction, have proven highly effective for their recovery. In addition, the application of elicitation strategies, such as salt stress, shading, hormones, and microbial biostimulants, has emerged as a promising approach for enhancing the production of these compounds during cultivation. Therefore, this review highlights Cynara as a valuable source of sesquiterpene lactones with broad applications in medicine and agriculture and provides guidance on technical approaches relevant to their extraction and the enhancement of their production.